Research Description

Optimizing the Volatilization of Mercury in Chlor-Alkali Wastewaters

Mercury is a known toxin to humans and the environment. The majority of mercury is introduced to the environment through anthropogenic sources such as coal fired power plants and waste incinerators. Other sources of mercury, particularly through water discharge, originate from chlor-alkali plants. The most toxic type of mercury takes place in its organic form as methylmercury. In this phase, it bioaccumulates in fish tissue - thus being in greater concentrations at the time of human consumption. Consuming fish with large amounts of mercury is proven to be toxic through evidence of the neurological damage it causes to fetuses that were exposed.

In order to prevent the accumulation of mercury in the environment, this research aims to focus on the wastewater discharges from chlor-alkali facilities. The objective of this research is to focus on the photoreduction of mercury in order to decrease the solubility of mercury in the water. Elemental mercury has a low solubility and can be volatilized via air or nitrogen stripping. Optimizing the volatilization of mercury can be accomplished by changing the UV wavelength and the purge gas. Wavelengths of 254 nm and 365 nm will be used. Each wavelength will be exposed to a purge gas altering between nitrogen and air. The concentrations of mercury within each of these reactors containing a UV lamp and purge gas will be 50 ppb, 100 ppb, 500 ppb, and 1000 ppb. The quantity of mercury volatilized for each parameter will be used to determine the optimal conditions.